To achieve good video streaming performance, one issue that is typically addressed is how to mitigate the packet loss impact from imperfect network transmission. For this problem, a general and efficient framework that has been applied is end-to-end distortion (ED) based rate-distortion (RD) optimization (ED-RDO). To improve the error resilience of video encoding, a variety of ED-RDO based techniques have been proposed. In the video transport modules, ED-RDO has been applied to optimize the selection of packet delivery policies. To achieve good ED-RDO performance, one challenge is how to accurately estimate the ED.
Typical ED estimation schemes, that operate on a sub-frame level, estimate the ED of the current frame by considering the error propagation from all the past frames up to the current frame. Errors may propagate, for example, because of inter-frame coding in which a current frame is compressed using a previous frame as a reference frame. Thus, if there is an error in the reference frame, then the current frame will also reflect the error. Other ED estimation schemes, that operate on a frame-level, estimate the ED of the current frame by considering errors in future frames that are attributable to an error in the current frame.